Various types of display devices, such as a cathode ray tube (CRT), a liquid crystal display (LCD), and a plasma display panel (PDP), which are to be used for a high-definition and large display television, have been developed.
The PDP includes phosphor layers for emitting three primary colors, red (R), green (G), and blue (B) so as to perform full color display by adding and mixing three primary colors (red, green, and blue). The PDP has a discharge cell, and generates visible light by exciting phosphor layers with ultraviolet rays generated by a discharge in the discharge cell, thereby displaying an image.
In an AC type PDP, an electrode for main discharge is generally covered with a dielectric layer, and performs memory driving to reduce a driving voltage. When the dielectric layer deteriorates due to an impact of ions generated by the discharge and hitting the layer, the driving voltage may increase. To prevent this increasing, a protective layer for protecting the dielectric layer is formed on a surface of the dielectric layer. For example, a protective layer made of material having high sputtering resistance, such as magnesium oxide (MgO), is disclosed in pp. 79-80 in “ALL ABOUT PLASMA DISPLAY” co-authored by Hiraki Uchiike and Shigeo Mikoshiba, published by Kogyo Chosakai Publishing Inc. in May, 1, 1997.
The conventional PDP structured may provide the following problem. In the PDP, a pulse of a driving voltage is applied to the electrodes for generating a discharge in the discharge cell. This discharge may delay from the rising of the pulse by a period of time, “a discharge delay time”. This discharge delay time may decrease a probability of end of the discharge depending on driving conditions while the pulse is applied. As a result, an electric charge may not be stored in a discharge cell to illuminate actually, thereby causing illumination failure and having quality deteriorate.